IBIC2016 - List of Authors (Gasior, M.)

Paper	Title	Page
MOPG07	First Operational Experience with the LHC Diode ORbit and OScillation (DOROS) System	43
	M. Gąsior, G. Baud, J. Olexa, G. Valentino CERN, Geneva, Switzerland
	The LHC started high-energy operation in 2015 with new tertiary collimators, equipped with beam position monitors embedded in their jaws. The required resolution and stability of the beam orbit measurements linked to these BPMs were addressed by the development of a new Diode ORbit and OScillation (DOROS) system. DOROS converts the short BPM electrode pulses into slowly varying signals by compensated diode detectors, whose output signals can be precisely processed and acquired with 24-bit ADCs. This scheme allows a sub-micrometre orbit resolution to be achieved with robust and relatively simple hardware. The DOROS system is also equipped with dedicated channels optimised for processing beam oscillation signals. Data from these channels can be used to perform betatron coupling and beta-beating measurements. The achieved performance of the DOROS system triggered its installation on the beam position monitors located next to the LHC experiments for testing the system as an option of improving the beam orbit measurement in the most important LHC locations. After introducing the DOROS system, its performance is discussed through both, beam and laboratory measurements.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG07
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MOPG49	A Precise Pulsed Current Source for Absolute Calibration of Current Measurement Systems With No DC Response	165
	M. Krupa, M. Gąsior CERN, Geneva, Switzerland M. Krupa TUL-DMCS, Łódź, Poland
	Absolute calibration of systems with no DC response requires pulsed calibration circuits. This paper presents a precise pulsed current source designed primarily for remote calibration of a beam intensity measurement system. However, due to its simple and flexible design, it might also prove interesting for other applications. The circuit was designed to drive a load of 10 Ω with current pulses lasting a few hundred microseconds with an amplitude of 1 A and precision in the order of 0.01%. The circuit is equipped with a half-bridge for precise determination of the absolute output current using the 0 V method. This paper presents the circuit topology and discusses in detail the choice of the critical components along with their influence on the final achieved accuracy. The performance of the built prototype of the current source is presented with laboratory measurements.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG49
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WEAL02	The Wall Current Transformer - a New Sensor for Precise Bunch-by-Bunch Intensity Measurements in the LHC	568
	M. Krupa, M. Gąsior CERN, Geneva, Switzerland
	The Wall Current Transformer (WCT) is a new bunch-by-bunch intensity monitor developed by the CERN Beam Instrumentation Group to overcome the performance issues of commercial Fast Beam Current Transformers (FBCT) observed during Run 1 of the LHC. In the WCT the large magnetic cores commonly used in FBCTs are replaced with small RF transformers distributed around the beam pipe. Rather than directly measuring the beam current, the WCT measures the image current induced by the beam on the walls of the vacuum chamber. The image current is forced to flow through a number of screws which form the single-turn primary windings of the RF transformers. The signals of the secondary windings are combined and the resulting pulse is filtered, amplified and sent to the acquisition system. This paper presents the principle of operation of the WCT and its performance based on laboratory and beam measurements.
	Slides WEAL02 [13.114 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEAL02
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Paper

Title

Page

First Operational Experience with the LHC Diode ORbit and OScillation (DOROS) System

43

M. Gąsior, G. Baud, J. Olexa, G. Valentino
CERN, Geneva, Switzerland

The LHC started high-energy operation in 2015 with new tertiary collimators, equipped with beam position monitors embedded in their jaws. The required resolution and stability of the beam orbit measurements linked to these BPMs were addressed by the development of a new Diode ORbit and OScillation (DOROS) system. DOROS converts the short BPM electrode pulses into slowly varying signals by compensated diode detectors, whose output signals can be precisely processed and acquired with 24-bit ADCs. This scheme allows a sub-micrometre orbit resolution to be achieved with robust and relatively simple hardware. The DOROS system is also equipped with dedicated channels optimised for processing beam oscillation signals. Data from these channels can be used to perform betatron coupling and beta-beating measurements. The achieved performance of the DOROS system triggered its installation on the beam position monitors located next to the LHC experiments for testing the system as an option of improving the beam orbit measurement in the most important LHC locations. After introducing the DOROS system, its performance is discussed through both, beam and laboratory measurements.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG07

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MOPG49

A Precise Pulsed Current Source for Absolute Calibration of Current Measurement Systems With No DC Response

165

M. Krupa, M. Gąsior
CERN, Geneva, Switzerland
M. Krupa
TUL-DMCS, Łódź, Poland

Absolute calibration of systems with no DC response requires pulsed calibration circuits. This paper presents a precise pulsed current source designed primarily for remote calibration of a beam intensity measurement system. However, due to its simple and flexible design, it might also prove interesting for other applications. The circuit was designed to drive a load of 10 Ω with current pulses lasting a few hundred microseconds with an amplitude of 1 A and precision in the order of 0.01%. The circuit is equipped with a half-bridge for precise determination of the absolute output current using the 0 V method. This paper presents the circuit topology and discusses in detail the choice of the critical components along with their influence on the final achieved accuracy. The performance of the built prototype of the current source is presented with laboratory measurements.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG49

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reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEAL02

The Wall Current Transformer - a New Sensor for Precise Bunch-by-Bunch Intensity Measurements in the LHC

568

M. Krupa, M. Gąsior
CERN, Geneva, Switzerland

The Wall Current Transformer (WCT) is a new bunch-by-bunch intensity monitor developed by the CERN Beam Instrumentation Group to overcome the performance issues of commercial Fast Beam Current Transformers (FBCT) observed during Run 1 of the LHC. In the WCT the large magnetic cores commonly used in FBCTs are replaced with small RF transformers distributed around the beam pipe. Rather than directly measuring the beam current, the WCT measures the image current induced by the beam on the walls of the vacuum chamber. The image current is forced to flow through a number of screws which form the single-turn primary windings of the RF transformers. The signals of the secondary windings are combined and the resulting pulse is filtered, amplified and sent to the acquisition system. This paper presents the principle of operation of the WCT and its performance based on laboratory and beam measurements.

Slides WEAL02 [13.114 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEAL02

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)